The present invention relates to a toilet paper roll of such a structure as does not require a conventional cardboard tubular core, and also to a method of manufacturing such toilet paper rolls.
Conventionally, toilet paper rolls are produced by winding or taking-up a toilet paper material, typically crepe paper, on a tubular core usually of a cardboard having a diameter normally on the order of 4 cm, to a roll size on the order of 14 cm in outside diameter. Toilet paper rolls are also usually manufactured by taking-up toilet paper material of a relatively great width on an accordingly long core to provide a half-finished toilet paper roll and then cutting or slitting the half-finished paper roll to provide toilet paper rolls of a width as prescribed. For purposes of definiteness in description, "an intermediate product (of toilet paper rolls)" is herein termed to mean such half-finished toilet paper roll.
As stated above, toilet paper rolls usually have a cardboard tubular core. If they can be produced without the need of using such a cardboard core, then an advantage is obtained in that the cost of the cardboard core is eliminated and, the cost of the production of toilet paper rolls can be reduced accordingly. A further advantage which is also realizable in the case of toilet paper rolls devoid of a cardboard tubular core is obtained in the use of toilet paper rolls in public conveniences, namely such lavatories as installed or provided in various public places and buildings, which are sometimes inconvenienced by cardboard cores of toilet paper rolls having been thrown into toilet bowls. Cardboard cores can not be flushed away and give rise to clogging in the toilet devices and/or drainage system. This inconvenience can be avoided if toilet paper rolls do not have the cardboard core. Moreover, if the cardboard cores, the diameter of which is normally on the order of 4 cm as stated above is dispensed with, there will be produced a central open space in the toilet paper roll, and the central open space may then be partly filled with an additional taken-up portion of the toilet paper to increase the amount or length of paper per roll without any increase made in the outside diameter of paper rolls. In the case of such toilet paper rolls, assuming that the paper is consumed in a constant amount each time of use, the time before a single toilet paper roll is used up can be prolonged or the frequency of required replenishment of toilet paper rolls can be reduced. Also, the number of toilet paper rolls to be constantly kept in stock according to for example household needs can be greatly reduced to accordingly save the space required for the stock or storage of paper rolls.
Then, Japanese utility model publication No. 54-43963 discloses an invention relating to such a toilet paper roll in which the tubular cardboard core is eliminated to avoid high production costs and the inconvenience of clogging toilet drain systems and which is prevented from undergoing a deformation likely due to the absence of a cardboard core. According to the invention disclosed in this publication, a toilet paper roll is produced in a manner such that in rolling toilet paper material on a take-up core of a very small diameter by applying pressure to the toilet paper being taken-up, a change is imparted to the pressure application so that a core layer portion of the paper roll is relatively loosely formed, then an outer layer portion is relatively tightly formed over such relatively loosely rolled core layer portion, and upon completion of the rolling-up of paper, the take-up core is pulled out of the formed roll of paper, to provide a toilet paper roll devoid of a core.
While the toilet paper roll is used with a rollsupport shaft or bar of a toilet-roll holder inserted through its central hole formed after the removal of the take-up core, with the paper roll according to the invention of the patent publication in reference, the inner layers of paper close to the small-diameter take-up core are relatively loosely rolled up as stated above and are therefore prone to deformation after removal of the take-up core. Thus when attempting to insert a roll support bar of the toilet roll holder increasingly deep into the hole through the paper roll, the support bar is moved in a manner which tends to peel off the innermost layer forming the wall of the hole, and it becomes difficult or troublesome or it requires a particular care to be exerted to smoothly insert the roll support bar.
Also, toilet paper rolls are produced and commercially distributed in mass, and they are not necessarily always handled carefully. If they are subjected to shock during handling, they tend to undergo deformation in their respective core layer portions if the core portions are loosely rolled up as above.
Then, with respect to devices for producing toilet paper rolls, conventional devices involve various problems in automatically continuously carrying out all of the steps of supplying cardboard take-up cores which are indespensably used in taking-up toilet paper material, of rolling-up a toilet paper stock on the take-up cardboard core, of cutting the paper after completion of the taking-up of the prescribed length of paper to provide an intermediate product of toilet paper rolls and of taking out the intermediate product, being a half-finished toilet paper roll.